Elastic-fluid turbine



r H. wm'r V ELASTIC FLUID TURBINE Filed Feb. 1, 1924 2 Sheets-Sheet l w W WE: l 4

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Patented Aug. 18, 1925. I

p uu ru sires HARRISON L. wins, or SCHENECTADY, new YORK, ASSIGNOR TO GENERAL ELECTRIC GOMPANY, A GOBIE'ORATION or NEW YORK.

ELASTIC-FLUID, rURBIivn.

Application filed February 1, 1924. Seriat No. 690,018.

To all whom it may concern:

Be it known that I, Hnunison L. 1m, a citizen oi"- the United States, residing at Schenectady, in the county of Schenectady, State of New York, have invented certain new and useful Improvements in Elastic- Fluid Turbines, of which the following is a specification.

The present invention relates to elastic fluid turbines of the type embodying a rotor provided with one or more rings of bucket elements, a plurality of such rings ofbucket elements being divided into groups, or arranged singly, to operate in successive stages, by partitions or diaphragms interposed between them. In turbines of this type, admission of elastic fluid from stage to stage is provided by fluid directing means or nozzles positioned in the diaphragms in alignment with adjacent rings of bucket elements.

Between certain of the stages the nozzles may cover all the bucket elements of the adjacent rings providing annular or full peripheral admission from one stage to the next succeeding stage, while between other stages and particularly between the elastic fluid inlet and the first stage, the nozzles may cover only a short are of bucket elements in each ring, thus providing partial peripheral admission from a preceding to a succeeding stage or from the inlet to the first stage, as distinguished from the full or completely annular admission above mentioned.

In a stage provided with partial peripheral admission, the bucket elements therein move through an arcuate elastic fluid stream directed therein by the less-than-annular admission nozzle section and are active for only that portion of their travel. For the remainder of their travel, the bucket elements move in space and tend to pick up or entrain in the form of a wake, the elasticfluid ordinarily present in and circulating about the stage. The Wake, thus formed, moves in the direction of movement of the bucket elements with considerable velocity and tends to collide with and impede the flow o'stthe elastic fluid stream issuing from the active arc of pzirtial admission.

The wake stream is broken in colliding with the elastic fluid exit stream and is thus prevented from filling in about the buckets as they leave the active arc. Losses in eiflciency of operation are introduced by frictional resistance and eddy currents 59b up.

In case the elastic fluid inlet nozzle carrying member projects into the stage in the path of the wake or in case more than one bucket ring is employed in the stage with an ntermediate or arcuate fluid directing means interposed; between such additional bucket ring and the first, the wake stream is further impeded by such stationary fluid directmg means and further losses are introduced thereby. Thus it will be seen that it 1s highly desirable to conserve the wake stream and atthe same time to prevent its collision with such fluid directing means as may be employed in a stage and with the exit stream of elastic fluid from the active arc of partial admission.

It is to turbines having one or more stages provided with partial peripheral admission that the present invention more particu-. larly relates, having for its object the provislon of an improved structure and arrangement in such stages whereby Wake streams, created by bucket rings and the like mov ing'in the space of the stage, may be conserved and supplied to the space about said bucket rings as they leave the active arc of admission, without interfering with the flow of'elastic fluid or colliding with certain fluid directing means which may be employed in the stage. I

Two embodiments of the invention are herein described and illustrated by way of example in connection with the first stage of an elastic fluid turbine, having a pair of closely associated rings of bucket elements 'moving in parallel relation with each other anda stationary arcuate fluid directing means or intermediate located between them.

For a consideration of what is believed to be novel and the invention attention is directed to the accompanying drawings, the

description of the particular embodiments of the invention illustrated therein and the appended claims.

In the drawing, Fig. 1 is a sectional end View of the first stage of an elastic fluid turbine embodying the invention, looking in the direction of the inlet; Fig. 2 is a sectional side view taken on line 2*2, Fig. 1., looking in the direction of the arrows; Fig. 3 is a plan View, partly in section, taken on line 3 3, Fig. 2; Fig. t is a sectional end view of a modification applied to the turbine stageshown in Figs. 1, '2 and 3 and corresponds to Fig, 1; Fig. ,5 is a sectional sid view, taken on line 5 5, Fig. 4, looking in the direction of the arrows, and Fig. 6 is a plan view, partly in section, taken on line 6-6, F 5.

Referring to Figs. 1, 2 and 3, 7 is a bucket wheel carrying a pair of spaced rings of radial bucket elements 8 and 9 on its periphcry. The wheel is carried by a shaft 10, which is the main shaft of the turbine, and revolves in a chamber or stage 11 formed in the high pressure end of the turbine casing. The turbine casing is indicated at 12 andthe stage formed therein, as shown, is the high pressure or first stage.

Themeans providing admission of elastic fluid to the first stage covers only a short arc of the bucket rings, being of the partial peri ')l1eral admission type. This includes an inlet conduit 13 having flanged ends 1d and 15, the latter end being'arc-shaped and recessed to form with an opening in the easing, an arcuate inlet chamber 16, a corresponding arcuate nozzle plate 17 forming one wall of said chamber within the casing adjacent bucket ring 8, and fluid directing means or nozzles 18 in the plate 17 in alignment with the bucket elements of ring 8.

Between bucket rings 8 and 9. in alignment with nozzles 18 and bucket rings 8 and 9, is a set of fluid directing members 19 carried inan arcuate frame 20. These members together with frame 20 form a fluid directing means or intermediate for the second ring of buckets 9 and together with nozzles 18 direct the elastic fluid supplied to the inlet chamber 16 through the stage in an arcuate stream. The nozzles 18 and fluid directing means 19 together with the bucket elements they cover provide in the stage what may be regarded as a working passage of arcuate form. The bucket elements in rings 8 and 9 thus move through a stream of elastic fluid for only portion of their travel in each revolution. For the remainder of their travel they are idle and move in free parallel relation in the stage 11.

Above the fluid directing means a passage or tunnel 21 is formed by a wall 22 of l..- shaped section inserted in the casing and held in place by bolts 23. The tunnel is arc-shaped, conforming with and lying in close-relation to the moving bucket rings 8 and 9. The frame 20, in which the intermediate fluid directing members 19 are formed, is supported from the lower horizontally extending portion of the wall 22. This wall extends slightly beyond the ends of frame 20.

The purpose of tunnel 21 is to bypass the wake entrained by the moving bucket rings, around or over the fluid guide means and elastic fluid stream entering the stage, that is, over the arcuate working passage, and feed it into the space about the bucket rings when they emerge from the working passage on the exit side of the'fluid guide means. Bypassing the wake thus takes away the wake from the Wheel at a point where it is no longer wanted and feeds it in again at a point where it is wanted, thus obviating eudy currents and frictional losses which would result if the wage vere to impinge against the fluid guide means, that is, against the frame 20 and the nozzle plate 17. It further prevents collision between the wake and the elastic fluid stream as it emerges from the second ring of buckets 9. Viewed in another aspect it provides a continuous free path for the wake about obstructions in its natural path and permits the wake to fill in the void which would otherwise exist about thebuck et rings as they leave the active are or elastic fluid stream.

To pick up and deliver to the tunnel 91 as much of the wake as can be used to advantage, the lower side of the tunnel, that is, the horizontally extending portion of wall is provided at its ends with integral plow-shapeijl members 21 which depend between and on either side ofthe bucket rings 8 and 9 in'close relation to-the same. Members 24. are provided in dup lcate at both the er-l t and entrant ends of tunnel 21 and are curvedon their upper faces as indicated at QS'toprovide a stream line fluid receiving means or scoop at the entrant end of the tunnel and a stream line fluid dispensing means or feeder at'the exit end of the tunnel. The direction of flow of the wake stream, as well as the direction of rotation, is indicated in Fig. 1 by suitably placed arrows.

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will. be seen that the wake stream i"; substantially deflected radially from its normal path between and around bucket ri 8 and 9 and carried in a smooth path or tun nel around the obstruction represented by the fluidgui-de means and working passage to a point beyond said fluid guide means in the direction of flow and again fed between and around the bucket rings as they emerge from the active portion of their travel. Thus the wake stream is conserved and losses incident to its interception are obviated.

Referring now to the modification, Figs. 4;, 5 and 6, l is the bucket wheel, 8 and 9 the rings of bucket elements carried thereby, 19 the turbine shaft and 12 the turbine earing. Elastic fluid is supplied to the turbine through inlet conduit 13 and is directed from inlet chamber 16 through the, stage wheels in an arcuate stream by fluid directing nozzles 18 and intermediate fluid dir g members 19.

The wheel and buckets operate in a single stage 11 and the arrangement is substantially that of the previously described embodiment. The wake stream entrained between and about the bucket rings 8 and 9 is picked up by plow-shaped members 24 at the entrant side of the active arc, deflected longitudinally by a stream line deflecting member 26 integral with casing 12 and again fed between and around the bucket rings by similar plow-shaped members 24 at the exit side of the active arc. The members 2-1 are, in this arrangement, integral with the deflector member 26 and the easing 12. They operate to scoop up the wake stream from the bucket rings or wheel on one side of the active arc and to feed it in about the bucket rings or wheel on the opposite side of the active are. Since the wake stream is, in this embodiment, not conlined in a tunnel in passing over the elastic fluid inlet stream and fluid guide means, stray portions of the wake stream, particu larly that portion following along on the low pressure side of ring 9, which would ordinarily intercept the elastic fluid stream issuing from the active arc, are prevented from doing so by wedge-shaped members 2? and 28 integral with the deflecting member 26.

Member 27 is located in the pat-h oi the wake stream about to collide with the elastic fluid stream and is so shaped that it divides or deflects the wake stream, causing the same to pass above and below the elastic fluid stream to the other side of the active are where member 28 is positioned to receive the split wake stream and by its stream line shape to unite the same into a single stream again.

In this embodiment of the invention, the frame 20, which carries the fluid directing intermediate members 19, is integral with he wake deflecting wall or member 26 and the nozzle plate 17 carrying nozzles 18 is fitted into a recess in the casing 12 below the deflector member 26.

In l'ioth embodiments of the invention, an arrangement is provided in a turbine stage for preventing the wake entrained between or about moving parts therein from impinging upon obstructions in its path such as the fluid guide means and the elastic fluid stream issuing therefrom. In each embodiment the wake is bypassed around the obstruction and maintained as a continuous stream.

The embodiment of the invention shown in Figs. 1, 2 and 3 is characterized by the fact that the wake stream is picked up and deflected radially over the obstruction in a confining tunnel, while that in Figs. t, 5 and 6 is characterized by the fact that the wake stream is picked up and deflected longitudinally in the open space of the stage by a member positioned over the obstructing fluid inlet means, that portion of the wake stream which would impinge upon the elastic fluid stream issuing from the second wheel being split to pass above and below said stream,

lVhile the invention has been herein described and illustrated in connection with the first stage 0t a turbine in which two parallel moving bucket rings are carried by a common wheel, it should be understood that it is not limited thereto, but may be applied to other turbine stages provider with. partial peripheral admission and having one or more moving bucket rings in such stages,

lVhat I claim as new and desire to secure by Letters Patent of the United States, is 1- 1. In an elastic fluid turbine, the combination with a rotor member, of a ring or bucket elements carried by said member, fluid-directing means for directing elastic fluid to said ring of bucket elements, the fluid-directing means being arcuate in form and covering an arc of said ring of less than 360 degrees whereby elastic fluid is directed to said in an arcuate stream, and means on opposite sides of the elastic fluid stream providing deflecting surfaces in the path of wake streams entrained by the ring of bucket elements for directing said wake streams away from and around the arcuate elastic fluid stream.

E2. in an elastic fluid turbine, the combination with arotor member, of a ring of bucket elements carried by said member, fluid-directing means for directing e fluid to said ring of bucket elements the fluiddirecting means being arcuate in form and covering an arc oi said ring of less than 3-60 degrees whereby elastic fluid is directed ,to said ring in an arcuate stream, and

means on opposite sides of the elastic fluid stream providing deflecting surfaces in the path of wake streams entrained by the ring of bucket elements for directing the latter in a continuous stream away from and around the arcuate elastic fluid stream and the fluid-directing means.

3. An elastic fluid turbine comprisixg a high pressure stage, a bucket carrying member therein, ring of buckets on said mem her, an arcuate fluid-directing nembcr d jacent said ring, said fluid-directing mem' ber covering an arc of the bucket ring and forming therewith an arcuate working passage for elastic fluid within the st e, and means on opposite sides of the elastic fluid stream providing deflecting surfaces in the path of the wake streams created by the moving bucket elements for directing the latter in a continuous stream away from andv around the working passage and the means forming the same.

An elastic fluid turbine comprising a high pressure stage, a bucket wheel therein, a plurality of. rings of bucket elements carried by the wheel, an arcuate fluid-directing member between said rings, said fluid-directing member covering an arc of the bucket elements and forming therewith an arcuate working passage for elastic fluid within the stage, and means on opposite sides of the elastic fluid stream providing deflecting surfaces in the path of wake streams created by the moving bucket elements for directing the latter in a continuous stream away from and around the working passage and the means forming the same.

An elastic fluid turbine comprising a high pressure stage, a bucket wheel therein, a ring 0t bucket elements carried by the wheel, an arcuate fluid-directiire member adj acentsaid ring, said fluid-directing member covering an are of the bucket elements and forming; therewith an arcuate working passage for elastic fluid within the stage, and means fer deflecting wake streams created by the moving bucket elements away from and around the working: passage and the means forming the same, said deflecting means comprising a passage around the working passage and extending from one side thereof to the other in the direction of movement of the bucket elements, a stream line fluid receiving member at the entrant end of the passage and a stream line fluid dispensing member at the GXlt end of the passage.

6. An elastic fluid turbine comprising: a high pressure stage, a bucket wheel therein, a ring of bucket elements carried by the wheel, an arcuate fluid-directing member adjacent said ring, said fluid-directing member covering an arc of the bucket elements and forming therewith an arcuate working passage for elastic fluid within the stage. means for deflecting wake streams created by the moving; bucket elements away from and around the working' passage and the means forming the same, said deflecting: means comprising a passage lying around the working passage and extending; from one side thereof to the other in the direc tion of movement of the bucket elements, and curved plow-shaped entrant and exit members for said passage depending from a wall of said passage on either side of and adjacent the ring of moving bucket elements.

7. In an elastic fluid turbine, the combination with a rotor member, of a ring of bucket elements carried by said member, fluid-directing means for directing;- elastic fluid to said ring of bucket elements, the fluid-directing means being arcuate in form and coveringan arc of said ring of less than 360 degrees whereby elastic fluid is directed to said ring in an arcuate stream, means for deflecting wake streams entrained by the ring of bucket elements away from said bucket elements at one side of the elastic fluid stream, means providing a path for said deflected wake streams around the elastic fluid stream to the opposite side thereof in the direction of rotation of the ring of bucket elements, and means at said opposite side for directing the deflected wake streams to the bucket elements.

8. An elastic fluid turbine, comprising: a high pressure stage, a bucket wheel therein, a plurality of rings of bucket elements car- 'ied by the wheel, an arcuate fluid-directing member between said rings, said fluid-directing member covering an are 01" the bucket elements and forming therewith an arcuate working-passage for elastic fluid within the stage, means for deflecting wake streams entrained by the ring of bucket elements away from said bucket elements at one side of the elastic fluid stream, means providing a path for said deflected wake streams around the working passage to the opposite side thereof in the direction of rotation. of the ring oi: bucket elements and means at said opposite side for directing the deflected wake streams to the bucket elements.

9. The combination with an elastic fluid turbine having a stage, a moving bucket ring; therein and means providing; partial peripheral admission to said bucket ring within the stage, of means for lay-passing around the admission n'ieans in a continuous stream-line flow, the wake streams set up and entrained by the moving bucket ring, said last-named means comprising" streamline deflector members positioned in the wake streams on opposite sides of the admission means adjacent said bucket ring.

10. The combination with an elastic fluid turbine having a stage, a moving bucket ring, therein and means providing partial peripheral admission to said bucket ring within the stage, of means for by-passinp; around the admission means in a continuous stream-line flow, the wake streams setup and entrained by the moving; bucket ring, said last-named means comprising streamline deflector members positioned in the wake streams on opposite sides of the admission means adjacent said bucket ring, said members on one side of the admission means presenting stream-line fluid deflecting surfaces to the wake streams to direct the latter away from said admission means and the bucket ring, and said members on the opposite side of said admission means presenting stream-line fluid dispensing surfaces to the deflected wake streams to deflect the same to the bucket ring.

In witness whereof, I have hereunto set my hand this 31st day of January, 1924;.

HARRISON L. iVIPT. 

